Surveillance cameras are widely used in public places such as factories, dorms, stores, or communities for recording evidence of any possible criminal activity. Thus, the surveillance cameras are able to prevent crimes from occurring and solve crimes by providing valuable evidence to the police.
There are two common types of surveillance cameras: a wide viewing-angle surveillance camera and a bullet-shaped surveillance camera. The wide viewing-angle surveillance camera is able to focus on a relatively wide area since it has a wide viewing angle, thus it is usually directly mounted on the wall or the ceiling by screws.